Diabetic retinopathy is the leading cause of blindness in working age Americans. In these patients there is pathologic growth of new blood vessels in the inner retina. These poorly formed blood vessels burst, bleeding into the retina and obscuring vision. Current treatment for these patients is to detect the neovascular formations and ablate tissue around the vessels, intending to reduce or eliminate further angiogenic response. It is proposed that new blood vessels are formed in response to local tissue hypoxia, but it is not possible at this time to identify focal areas of hypoxia in the retina. Oxygen Enterprises has developed a safe, accurate and robust method that is capable of detecting focal hypoxia in tissues. Through this Phase I SBIR Grant, the company proposes to apply their technology to the understanding and measuring oxygen in the retina of the eye. Initial application will be in biomedical research. Longer term goals will be to apply this technology into clinical practice, allowing clinicians to diagnose and treat patients with diabetic retinopathy earlier and more effectively. The company proposes to develop a phosphorescence lifetime imaging system that will provide an opticalmethod for the clinician that yields a topographic map, clearly identifying focal areas of hypoxia and differentiating them from areas of normoxia. During Phase 1 the company proposes to synthesize gram quantities of a new Oxyphors (phosphor) for suitable for pre-clinical testing and to construct a minimally invasive imaging system for use in ophthalmological research. The imaging system will be assembled and adapted for measuring oxygen in the retina of two animal models, piglets and rats, and the existing imaging software will be revised into a technically competent and user-friendly operating system. Oxygen Enterprises' imaging system is expected to offer sensitive and specific detection and quantification of focal hypoxia in retinal tissue - which is anticipated to allow earlier and more accurate diagnosis of retinopathy - and a diagnostic system with high stability and reliability, providing a clear and unambiguous display of retinal pathology. Emphasis will be on making the system user friendly and on providing it at a reasonable cost.